Transferor wheel and method of making same



Jan. 21, 1969 H. E. RAHM ET AL 3,423,268

TRANSFEROR WHEEL AND METHOD OI MAKING SAME Filed April 19, 1967 Sheet of 2 INVENTORS HOWA RD E. RAHM DA V/D L. BR/MMER ATTORNEY Jan. 21, 1969 4 H. RAHM ET AL. Y 3,423,268

TRANSFEROR WHEEL AND METHOD OF MAKING SAME Filed April 19, 1967 Sheet 2 of 2 INVENTORS HOWARD E. RAHM v BY DAV/D L. BR/MMER fl fim ATTORNEY.

United States Patent 20 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a moisture and/or heat transferor wheel and to a method of making such a wheel. The wheel is made from a plurality of fibrous sheets, such as corrugated asbestos paper sheets, that have a flat portion and an undulating portion that form a plurality of parallel channels. An adhesive is applied to the peaks of the undulating portions and the sheets are laid on top of one another to form a block configuration. The sheets are laid in such a manner that the channels in all the sheets extend parallel to one another throughout the entire block and the ends of the sheets are aligned to form channels of equal length. Pressure is applied normal to the flat portions until such time as the adhesive throughout the block has set. After the adhesive takes hold, the pressure is removed and the block is cut into a wheel with the axis of the wheel extending parallel to the direction of the channels. The paper is treated with a liquid to provide it with wet strength. The wheel is then impregnated with a hygroscopic solution before being placed in a housing.

Through the method of this invention, it is possible to make a transferor wheel by forming sections and then joining the sections. The sections may be oriented so that the channels of all sections extend parallel to each other while the flat portions of one section extend at an angle to an adjoining section. With this construction, a wheel can be built having high compressive strength both longitudinally and radially.

Background Many devices are used for the conditioning, exchange of sensible heat, or the dehumidification or humidification of streams of air. These devices often employ a transferor wheel, a cylinder, made of fibrous material, such as single faced corrugated asbestos paper, impregnated with an active chemical solution. As used throughout this specification and the accompanying claims, the term transferor wheel is intended to include that class of wheels formed from a fibrous material that is treated to either humidify or dehumidify gases, act as a heat exchanger for both sensible and latent heat, or in any other way condition gases. These wheel-s rotate about their longitudinal axis and means is provided to drive the gas, usually air, to be conditioned longitudinally through the portion of the wheel that is rotating through a given zone, while the balance of the wheel has its chemical solution regenerated. Examples of such trans-feror wheels are shown in US. Patents 2,818,934 (N.'A. Pennington), 3,065,956 (G. W. Meek), and 3,155,153 (A. B. Axelsson), and Canadian Patent 719,247 (Lundquist). These prior devices rely either upon a method of forming the wheel by spirally winding paper about a central core or use of a plurality of radially extending spokes that support the paper. A shortcoming of the spiraling method is that the "ice in turn, is controlled by the tensile strength of the material. Consequently, if the paper has low tensile strength, then a weak wheel will result therefrom. In addition, the sheets of paper are aligned in only one direction so that the wheel has high compressive strength longitudinally, but low radial compressive strength. Furthermore, with wheels made by the spiral winding method, mechanical strength is reduced with increase in diameter because of the increase in weight of the wheel and inability to increase radial strength in proportion thereto. The chief drawback of the spoke construction is the presence of many joined surfaces, thus increasing the possibility of leakage therebetween, and the loss of absorption surfaces due to the presence of these spokes.

Objects It is, therefore, an object of this invention to provide a novel method of making a moisture and/ or heat transferor wheel.

It is another object of this invention to provide a wheel made of laminated paper sheets.

It is still a further object of this invention to provide a novel transferor wheel having high compressive strength both radially and longitudinally.

It is still another object of this invention to provide a method of producing a large diameter wheel having greater mechanical strength than has heretofore been possible.

It is a further object of this invention to provide a method of producing a transferor wheel by combining individually constructed sections.

It is a still further object of this invention to provide a wheel made of laminated paper sheets wherein a portion of the paper sheets has its flat surfaces disposed to an angle relative to another portion of the paper sheets.

Views of the drawing In the drawing:

FIG. 1 is a partially sectional, longitudinal view of a transferor wheel that embodies the principles of this invention.

FIG. 2 is a cross-sectional view of the wheel of FIG. 1 taken along the lines 22.

FIG. 3 is an end view of the wheel of FIG. 1 taken along the lines 33.

FIG. 4 is an enlarged cross-sectional view of corrugated sheets that are used to form the transferor wheel of FIG. 1.

FIG. 5 is a cross-sectional view of an embodiment of the wheel of FIG. 1 taken along the lines 2-2.

Detailed description of the invention Referring now to the drawing, a transferor wheel is shown at 10 comprising a plurality of corrugated sheets 12 received within an annular sleeve 13. Each sheet is made from an undulating portion 14 and a flat portion 16 having a first major surface 18 and a second major surface 20; The undulating portion 14 is attached to the first major surface 18, thereby providing a plurality of open end channels 22 between the undulating and flat portions. The channels extend longitudinally parallel to one another along the entire length of the wheel 10.

The transferor wheel 10 shown in FIG. 2 is made up of a plurality of sections 24, 25 and 26. In the particular embodiment shown, two of the sections 24 and 26 have their flat portions 16 extending parallel to one another, with the section 25 intermediate these two other sections having its flat portions 16 extending perpendicularly to the direction of the fiat portions of the other two sections. The channels 22, however, in all of the sections extend in the same direction. The sections 2424 are attached to one another in a manner so that flat ends 28 and 30 are provided to the Wheel 10. The ends 28 and 30 are covered with a protective net 32, as for example Teflon coated fiber glass, to prevent wear on the paper as it is engaged by parts of a sealing member 36. The protective net 32 is held against the ends 28 and 30 by being attached to annular shoulders 34 that are secured to the sleeve 13. The shoulders 34 are made of a lightweight metal, such as aluminum. The seal member 36 is part of the housing that receives the wheel and has means for directing two streams of air, which housing forms no part of this invention and is not shown. The seal member 36 segregates a portion of the wheel from the remainder of the wheel by engaging the net 32. In this way, the air to be conditioned is directed through the channels in three-quarters of the wheel, whereas those channels in the quadrant defined by the seal member 36 are regenerated by hot air that is blown through the channels in this quadrant.

In the preferred method of constructing the wheel 19 of this invention, glue is applied to the peaks of the undulating portion 14 of the sheets 12 and these sheets are superimposed on one another with the undulating portions 14 of each sheet engaging the fiat portion 16 of its adjacent sheet. The sheets 12 are laid so that open end channels are formed 'by the corrugations that define separated air passageways parallel to one another and Whose ends are aligned to form flat faces 28 and 30. Pressure is applied perpendicularly relative to the flat portion 16 along the entire plane of these sheets 12 so that they are firmly pressed together. After the glue sets, the pressure is removed from the now-formed section of sheets. At this point, a plurality of sections may be glued together to form a single large block or a single section may be used. The edges of the block or section are cut to form a cylindrical wheel whose axis is parallel to the direction of the channels and the wheel is placed in the sleeve 13. The wheel is then impregnated with a strengthening agent to give it wet strength. Examples of such strengthening agents are resins, such as phenol-formaldehyde, and various epoxies. In the preferred embodiment, the cylindrical wheel is soaked with an aqueous solution of sodium silicate until thorough penetration is achieved. The wheel is drained and then immersed into a solution of calcium chloride. A chemical reaction takes place whereby calcium silicate and sodium chloride are formed. The sodium chloride and clacium chloride are water soluble and easily removed from the wheel, leaving only the insoluble calcium silicate which serves to impart wet strength to the paper. The wheel 10 is then immersed in an aqueous solution of lithium chloride to give it hygroscopic properties necessary for dehumidification.

After the chemical treatment is complete, the net 32 is placed against the ends 28 and 30 and held securely to the shoulders 34. The hygroscopic wheel is placed in the housing and means is provided whereby the wheel is rotatable about its axis.

In wheels of relatively small diameter, in the range of 8 to 24 inches, the wheel may be made from a single section with the corrugated sheets extending parallel to one another throughout the wheel, since the strength requirements for a small wheel are not demanding. For large wheels, however, it is preferable that each be made from a single block composed of a plurality of sections, which block is then cut to form a wheel.

High compressive strength in both radial and axial directions may be imparted to a wheel by having it made from a plurality of sections that are joined together rather than in a single section. The sections may he oriented so that the flat portions 16 of each section extend in a variety of directions to impart strength to the wheel throughout, rather than having all the flat surfaces run parallel to each other.

Examples of different orientation are shown in FIG. 2 where the wheel 10 is made in sections 24-26, each section defining a portion of a cylindrical surface. Each section has greater resistance to a force directed parallel to the flat portions 16 than to a force directed normal thereto. Hence, when a radial force is directed toward the Wheel at any of the sections, there is greater resistance to that force. This increased resistance to a radial force is important during fabrication of the wheel 10, before it is placed in the sleeve 13, and is particularly useful in preventing bowing and crushing of parts of the wheel 10. Even more importantly, the angular orientation imparts increased mechanical strength to the Wheel and results in greater endurance.

It is apparent that a multitude of designs of the wheel may be achieved by the joining of sections in the manner described. Although only three sections are used in FIG. 2, it is obvious a greater or lesser number of sections with various orientations may be used. An example of such variations is shown in FIG. 5 where some of the sections 26a have a rectangular configuration and others, 24a and 25a, have a semi-cylindrical configuration. The combinations of orientation are many-fold and may be varied to achieve any particular purpose desired.

Although only a few embodiments of this invention have been shown and described, it is understood that changes and modifications can be made therein, and this description is illustrative only and not for the purpose of rendering this invention limited to the details illustrated or described except insofar as they are limited by the terms of the following claims.

We claim:

1. In a method of making a fibrous transferor wheel, the steps comprising: taking a plurality of corrugated sheets, each sheet having a fiat portion with first and second major surfaces and an undulating portion attached to the first major surface at spaced intervals to form a series of parallel channels, applying adhesive to the peaks of the channels, superimposing the corrugated sheets on one another with the undulating portion of one sheet in engagement with the second major surface of an adjoining sheet, and with the channels of substantially all the sheets extending parallel to one another, applying pressure perpendicularly relative to the flat portions until the adhesive sets, and cutting a cylindrical wheel therefrom whose axis extends parallel to the channels.

2. The method of claim 1 including the step of providing wet strength to said sheets by impregnating it with a strengthening material.

3. The method of claim 1 including the step of providing wet strength to the sheets by soaking them in a solution of sodium silicate, draining the wheel, then immersing in a solution of calcium chloride.

4. The method of claim 1 including the step of impregnating the sheets with a hygroscopic solution.

5. The method of claim 4 including the step of strengthening the sheets prior to impregnation with hygroscopic solution by soaking them in a solution of sodium silicate, draining the wheel, then immersing in a solution of calcium chloride.

6. In a method of making a fibrous transferor wheel, the steps comprising: making a first section by taking a plurality of corrugated paper sheets having a flat portion with first and second major surfaces and an undulating portion attached to the first major surface at spaced intervals to form a plurality of parallel channels, applying to the peaks of said undulating portion, superimposing one layer of corrugated sheet upon another so that the undulating portion of one sheet engages the second major surface of another sheet with the channels extending parallel to one another, applying a pressure to said corrugated sheets in a direction perpendicular relative to the flat portion and maintaining said pressure until the adhesive sets, making at least one more section in the same manner as the first section, attaching at least two sections to one another in a manner such that the channels of the combined sections extend parallel to one another and the flat portions of one of the sections extends at an angle relative to the flat portions of another section, and cutting the combined structure into a wheel whose axis extends parallel to said channels.

7. The method of claim 6 wherein said angle is 90".

8. The method of claim 6 including the step of providing wet strength to said sheets by impregnating them with a strengthening material.

9. The method of claim 6 including the step of soaking said sections in a solution of sodium silicate, draining the sections, then immersing in a solution of calcium chloride.

10. The method of claim 6 including the step of impregnating the sheets with a hygroscopic solution.

11. The method of claim 10' including the step of strengthening the sheets prior to impregnation with hygroscopic solution by soaking them in a solution of sodium silicate, draining the wheel, then immersing in a solution of calcium chloride.

12. The method of claim 6 including the step of cutting the ends of the combined structure to provide a flat face on at least one end of the wheel.

13. In a method of making a fibrous transferor wheel, the steps comprising: making a first section by taking a plurality of corrugated sheets having at least one flat portion and at least one undulating portion, which portions cooperate with one another to form a plurality of channels extending parallel to one another, superimposing the sheets upon one another "With the channels of substantially all the sheets extending parallel to one another, attaching the sheets to one another, making at least one other section in the same manner as the first section, attaching at least two sections to one another in a manner such that the channels of the attached sections extend parallel to one another, and cutting the combined structure into a wheel whose axis extends parallel to said channels.

14. The method of claim 13 wherein said sheets are superimposed on one another in a manner such that the flat portions of one section extend at an angle relative to the fiat portions of another section.

15. The method of claim 14 wherein said angle is 16. The method of claim 14 including the step of providing wet strength to said sheets by impregnating them with a strengthening material.

17. The method of claim 14 including the step of soaking said sections in a solution of sodium silicate, draining the sections, then immersing in a solution of calcium chloride.

18. The method of claim 13 including the step of impregnating the sheets with a hygroscopic solution.

19. The method of claim 18 including the step of strengthening the sheets prior to impregnation with hygroscopic solution by soaking them in a solution of calcium chloride.

20. The method of claim 14 including the step of cutting the ends of the combined sections to provide a flat face on at least one end of the wheel.

References Cited UNITED STATES PATENTS 2,818,934 1/1958 Pennington -10 X 2,986,379 5/1961 Kramig 261-112 X 3,231,409 1/ 1966 Munters 117-46 3,265,550 8/1966 Lindqvist 261-112 X 3,367,404 2/1968 Johnson et al 165--10 X ROBERT A. OLEARY, Primary Examiner. ALBERT W. DAVIS, Assistant Examiner.

US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,423,268 January 21, 1969 Howard E. Rahm et al.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 64, after Column 1, line 47, a" should read or "applying insert adhesive Signed and sealed this 17th day of March 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

